Frame for stretching canvases and the like



Jan. 30, 1923. 1,443,923. H.NERCAM.

FRAME FOR STRETCHING CANVASES AND THE LIKE.

' FILED JULY 9. I920.

'stantine, Algerie,

' and edges cross-bar, or bars,

Patented Jan. 30, 1923.

UNITE STAT" HENRI NERCAM, or oomsrniv'rrnn, ALGERIE, rnaiton.

V FRAME FOR STRETCHING CANVASES AN'D LIKE. 3

Application filed July 9, 1920 Serial "No. 395,145? V To all whom it may concern: Y Be it known that HENRI NERCAM, citizen of the Republic of France, residing at Con- France, 36 Avenue Bienfait, has invented certain new and "useful Improvements in Frames for' Stretching Canvases and the'like, of which the followin is a specification.

This invention relates to improvements in extensible stretching frames for holding and stretching various sizes of sheets, paintingcanvas, papers and similar materials, and its object is to provide a longitudinally and laterally, or two-way extensible frame in which no recesses occur at the four corners supporting the canvas or sheets on the extended frame. This frame comprises four corner bars connected together at the corners by mortice and tenon joints and formed with overlayed sliding arms with unilevel supportingedges' and permanently assembled corner pieces.

In large frames, where it is requiredin consideration of their size, an extensible may be provided. ach corner bar comprises two arms in tegral with mitre pieces having the full width and thickness of a complete bar and of any suitable length limited only by the strength which must be left for. the provision of the mortices and tenons or keys for as-' sembling the mitre corners. The corner portions form shoulders or stops for the sliding arms of the frame and/ their outer; bearing surfaces conform to those of the arms, while the outer bearing edge of all the members of the frame always preserve an uninterrupted uniform alignment. To render the invention clear I will describe the same fully with reference to the accompanying drawings, in which: v

Figure 1 is a front elevation slightly shown in perspective, of the complete frame in a partly extended condition. t

Figure 2 is a transverse section taken on the line 22 of Figure 1 shown to a larger scale.

Figure 3 is a perspective View showing the assemblage of the cross-bar to the frame portion The angle bars 1 and 2 are arranged so as to slide along one another and with closed frame they show a uniformly shaped'face, that is to say, the closed frame has an un interrupted border portion and recessed head which has longitudinal slots 3.

shall have aligned be at least two in number.

The corner pieces stand up flush with the outer arm 'ofeach bar and are morticed'to receive: the tenonsor tongues 51 and keys '5 I so as to provide" rigid corner points. The arms 1 have the border portionsfiundercut song to forman acute angled edge 7, 'se-e 31 Figure 2. The arms 2 are recessed so as-t o form a'bed for the arms 1 and havea wedge-shaped ledge or check 8 with knife edge 9 raised to meet the edge 7, as is clearly shown in F igure2. An essential feature of the invention is that the" extended frame bearer edges for the canvas or other material.

The sliding arms can in an adjusted position by screw bolts formed with a fiat square head 19 and insorted in corresponding slots 3 of the sliding arms. The latter may be markedv so as be" firmly retained to facilitate accurate adjustment. 7'

fitted with extensible Large frames are cross bars composed of three parts 10, 11, 12

of which the part 10 is the parts 11 and 12' extend for half such length. The parts 11 and 12 are removably' connected to the bars of the frame andj held rigid by wedges 16, their ends being slotted as at 15 to engage with a filling piece18 while bolts 17 allow for displace ment, see Figure 3. Corresponding slots 13 in the parts 10, 11 and 12 receive bolts '14 and together form'means permitting of lateral extension of the ame. g

The space which will separate each slot of length to fit bei i tween the closed bars 'ofthe frame, while from the next is optional and decided particularly by the solidity which must beleft to the sliding bars.

The length of the slots is likewise ops tional and will likewise be determined by the solidity necessary for the bars nevertheless it should be at least that of thespace left between successive slots plus twice the 7 diameter of the assembly bolts so that by the movements of extension or shortenin there will always be found openings permitting the assemblybolts topass through the thickness of the bars.

It follows that the width to'give to the slots will be equivalent to the diameter of the bolts together with a slight play. The

bolts to be used should preferably have flatQ heads; convenient length and thickness and To constitute a complete frame, four cor ner bars are assembled after-having been holding and stretching various sizes of; paint-- frame in order to assure an roughly arranged for the desired length as is done for ordinary wedge frames and there will be fixed to its outer edge by pins or brads the sheets vor paper for stretching.

Having described my invention, what I claim is t v 1. In an extensible stretching frame for tially as described.

2. In an extensible stretching frame for comprising holding-and stretching varioussizes ofpaintn1 canvases, angle bars to slide along one another to form a closed extensible frame,

mitre corners for them,,vmortiees and tenons for assembling the Initre corners, said bars lower armsrecessed to form a wedge edged bed for the upper bars, undercut border portions you the upper bars to fit the recesses of the lower arms to obtain aligned bearer edges all. around the -frame and to secure thereby an absolutely plane surface of the stretched canvas, and means to fix the arms in the adjusted position,substantially as described. 7

In testimony whereof he has affixed his signature in presence of two witnesses.

a. p HENRI NERCAM. Witnessesi 4 i i D. C. ELKINGTQN,

JLMICALLY. I 

